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==== Report for the week of 3/11 ====
 * Fabian helped Fujii-kun with the PRM most of the week. Hirata-san also helped at various times.
 * Fabian monitored the SRM yaw drift. It gradually reversed but so far remained small. We will try resetting it to zero with the pico and see if the trend changes.
 * Mark and Hirata-san debugged the BS:
  * We inspected the payload section and quickly found the problem: two RM EQ stops were touching, on the +L (-X,+Y) side at the top. This was probably because the stops had been adjusted with the IP unlocked and sitting a few mm to -L, whereas now we have the DCCTRL running and have been locking the IP at the LVDT zero. We drove the IP to L=+1.5 mm as a near-worst case, and backed off all the stops to give several mm of margin. Then we zeroed the IP pitch, roll and yaw with the picos.
  * We also opened the top of the BS and confirmed that the mechanical zero defined by the locking mechanism agreed with the LVDT zero. It was very close in L and T, but -728 µrad in Y, driven mostly by a -805 µm offset in H3. That much is probably not a dumb error but just a difference in technique among the three people using calipers to take data for the calibration.
  * We then prepared the BS for close-up:
   * We wiped and inspected the O-ring for the lid and replaced the lid.
   * We wiped all accessible surfaces in the lower half of the tank, rescued some dropped items (some PEEK tube and a small nut) and un-immobilized the LBB.
  * After all the above, the OL was a bit off-center but still on the QPD, and Nagano-san fairly quickly recovered the original alignment.
==== Report for the week of 4/8 ====
 * Support of Type Bp
  * Mark made lots of Guardian improvements:
   * Used Guardian's timer functionality to drastically reduce the number of notifications during ramping.
   * Added new requestable states DCCTRL_ONLY and NEUTRAL (and associated transitional states) to facilitate testing.
   * Tidied up the code to use tabs consistently throughout for indentation.
   * Disabled the test for the IM-H coil driver WD (to work around the fact that only the relay in the chassis has been disabled, not the WD signals going to the BIO).
 * We opened the BS tank lid and offloaded a large IM-Y offset to F0-Y with manual adjustment of the broken yaw mechanism).
 * We opened the SR2 side doors and adjusted the V1 OSEM to mid-range.
 * Mark offloaded a large SR2 IM-Y offset to F0-Y.
 * Mark did health checks for BS, SR2 and SR3.
 * Fabian offloaded yaw from SRM and did the SRM health check.
 * Fabian updated the Python code for the stepper driver MEDM screen to reflect that two stepper drivers have different mappings to work around dead channels.
 * Fabian monitored pumpdown on Friday afternoon and will continue on Saturday.
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 * Terrence rebuilt the BS TILT OL according to a new layout suggested by Simon, which avoids scrambling the pitch/yaw at the first steering mirror and greatly reduces the amount of diagonalization required. He started on the LEN OL, but unfortunately the QPD stage fell and bent the brackets holding two of the micrometers. It's useable but we haven't installed it yet.
 * Terrence noticed some anomalous cross coupling on the SR2 (but not the SR3) and we investigated.
  * We suspected it might be an odd position of the beam spot on the optic, so we took pictures through the camera and LED viewports of SR3, and opened the SR2 tank and used a white target, but the beam spots were in very similar positions - close to central vertically and about 3 cm to the left of center horizontally.
  * We suspected it might be something touching at the IRM (because the IM OSEM TFs were fine), so we checked using a stick mirror with the IP centered, but all EQ stops were well backed off.
  * We suspected it might be a ghost beam from the LEN/TILT beamsplitter (and one was clearly visible on the SR2 TILT QPD) so Terrence set up a beam block, which improved things slightly but not completely.

  * Finally Terrence discovered that the problem was mainly uneven sensitivities of the QPD quadrants, and devised a new calibration procedure which allowed for it. Later we discovered that one of the 3 dB gain stages on the whitening filter was engaged, even though the switch on the BIO Config card was not. It mysteriously came good after we removed and replugged the BIO Config card.
 * Enzo and Terrence did a health check of the SRM and it was fine except for some apparent electrical noise around 240 Hz. They put in a low-pass filter to get rid of it for now.

==== Plan for week of 3/18 ====
 * Mark, Fabian, Terrence at Kamioka full week.
 * More OL stuff.
  * SRM OL setup.
  * Recalibration of all OLs per new procedure.
  * Improve mounting of BS OL RX breadboard.
  * Reinstall BS LEN OL.
 * SRM controls and Guardian.
 * Reset SRM yaw and continue monitoring yaw drift.
 * Length/pitch decoupling.
 * Assist with pump down.
==== Plan for week of 4/15 ====
 * Mark, Hirata-san at Kamioka Tue-Thu.
 * Fabian at Kamioka Mon-Wed.
 * All at f2f Meeting 4/19-21.
 * Post-pumpdown health checks.
 * Teach Hirata-san about the computer systems and control theory.
 * Work with Lucia to do blending of the IP LVDTs and geophones.
 * More Guardian improvements.
  * Update vistools.py (formerly LIGO sustools.py) for Type B and KAGRA, and have the TYPEB.py Guardian use it where appropriate.
  * Modify RT models and/or Guardian to revert to the SAFE state under control in all but the most extreme emergency situations (rather than suddenly shutting off all output).
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  * Throw out foil and other garbage.
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  * Pull out unused cables in cable tray near SR3.
  * Return all unused cables to tent.
  * Tidy up cables in rear of SR2 rack.
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 * Enzo at JPS then final vacation, 3/13-29
 * Terrence's last day, 3/29.
 * Mark at Mitaka 4/15.
 * f2f 4/19 (Friday), 4/20, 4/21.
 * Terrence's next visit from 4/18.
 * Fabian's vacation 4/26 to 5/10.
 * Mark's US vacation from 5/22 to 6/11.
 * Mark's final day 6/28.

Scraps of text for incorporation in the VIS Meeting Minutes

KAGRA/Subgroups/VIS/MeetingNAOJ

Type B (Mark)

Report for the week of 4/8

  • Support of Type Bp
    • Mark made lots of Guardian improvements:
      • Used Guardian's timer functionality to drastically reduce the number of notifications during ramping.
      • Added new requestable states DCCTRL_ONLY and NEUTRAL (and associated transitional states) to facilitate testing.
      • Tidied up the code to use tabs consistently throughout for indentation.
      • Disabled the test for the IM-H coil driver WD (to work around the fact that only the relay in the chassis has been disabled, not the WD signals going to the BIO).
  • We opened the BS tank lid and offloaded a large IM-Y offset to F0-Y with manual adjustment of the broken yaw mechanism).
  • We opened the SR2 side doors and adjusted the V1 OSEM to mid-range.
  • Mark offloaded a large SR2 IM-Y offset to F0-Y.
  • Mark did health checks for BS, SR2 and SR3.
  • Fabian offloaded yaw from SRM and did the SRM health check.
  • Fabian updated the Python code for the stepper driver MEDM screen to reflect that two stepper drivers have different mappings to work around dead channels.
  • Fabian monitored pumpdown on Friday afternoon and will continue on Saturday.

Plan for week of 4/15

  • Mark, Hirata-san at Kamioka Tue-Thu.
  • Fabian at Kamioka Mon-Wed.
  • All at f2f Meeting 4/19-21.
  • Post-pumpdown health checks.
  • Teach Hirata-san about the computer systems and control theory.
  • Work with Lucia to do blending of the IP LVDTs and geophones.
  • More Guardian improvements.
    • Update vistools.py (formerly LIGO sustools.py) for Type B and KAGRA, and have the TYPEB.py Guardian use it where appropriate.
    • Modify RT models and/or Guardian to revert to the SAFE state under control in all but the most extreme emergency situations (rather than suddenly shutting off all output).
  • Work on Type B paper.
  • Tidy up.
    • Gather and clean tools.
    • Gather and organize unused parts and fasteners.

Vacation/Travel Info

  • Mark at Mitaka 4/15.
  • f2f 4/19 (Friday), 4/20, 4/21.
  • Terrence's next visit from 4/18.
  • Fabian's vacation 4/26 to 5/10.
  • Mark's US vacation from 5/22 to 6/11.
  • Mark's final day 6/28.

KAGRA/Subgroups/VIS/TypeB/Minutes (last edited 2022-10-28 10:02:46 by fabian.arellano)